2 * Noise generation for PuTTY's cryptographic random number
14 DECL_WINDOWS_FUNCTION(static, BOOL, CryptAcquireContextA,
15 (HCRYPTPROV *, LPCTSTR, LPCTSTR, DWORD, DWORD));
16 DECL_WINDOWS_FUNCTION(static, BOOL, CryptGenRandom,
17 (HCRYPTPROV, DWORD, BYTE *));
18 DECL_WINDOWS_FUNCTION(static, BOOL, CryptReleaseContext,
20 static HMODULE wincrypt_module = NULL;
23 * This function is called once, at PuTTY startup.
26 void noise_get_heavy(void (*func) (void *, int))
29 WIN32_FIND_DATA finddata;
31 HCRYPTPROV crypt_provider;
32 char winpath[MAX_PATH + 3];
34 GetWindowsDirectory(winpath, sizeof(winpath));
35 strcat(winpath, "\\*");
36 srch = FindFirstFile(winpath, &finddata);
37 if (srch != INVALID_HANDLE_VALUE) {
39 func(&finddata, sizeof(finddata));
40 } while (FindNextFile(srch, &finddata));
44 pid = GetCurrentProcessId();
45 func(&pid, sizeof(pid));
47 if (!wincrypt_module) {
48 wincrypt_module = load_system32_dll("advapi32.dll");
49 GET_WINDOWS_FUNCTION(wincrypt_module, CryptAcquireContextA);
50 GET_WINDOWS_FUNCTION(wincrypt_module, CryptGenRandom);
51 GET_WINDOWS_FUNCTION(wincrypt_module, CryptReleaseContext);
54 if (wincrypt_module && p_CryptAcquireContextA &&
55 p_CryptGenRandom && p_CryptReleaseContext &&
56 p_CryptAcquireContextA(&crypt_provider, NULL, NULL, PROV_RSA_FULL,
57 CRYPT_VERIFYCONTEXT)) {
59 if (p_CryptGenRandom(crypt_provider, 32, buf)) {
60 func(buf, sizeof(buf));
62 p_CryptReleaseContext(crypt_provider, 0);
65 read_random_seed(func);
66 /* Update the seed immediately, in case another instance uses it. */
70 void random_save_seed(void)
76 random_get_savedata(&data, &len);
77 write_random_seed(data, len);
83 * This function is called every time the random pool needs
84 * stirring, and will acquire the system time in all available
87 void noise_get_light(void (*func) (void *, int))
93 GetSystemTime(&systime);
94 func(&systime, sizeof(systime));
96 GetSystemTimeAdjustment(&adjust[0], &adjust[1], &rubbish);
97 func(&adjust, sizeof(adjust));
101 * This function is called on a timer, and it will monitor
102 * frequently changing quantities such as the state of physical and
103 * virtual memory, the state of the process's message queue, which
104 * window is in the foreground, which owns the clipboard, etc.
106 void noise_regular(void)
111 MEMORYSTATUS memstat;
114 w = GetForegroundWindow();
115 random_add_noise(&w, sizeof(w));
117 random_add_noise(&w, sizeof(w));
118 w = GetClipboardOwner();
119 random_add_noise(&w, sizeof(w));
120 z = GetQueueStatus(QS_ALLEVENTS);
121 random_add_noise(&z, sizeof(z));
124 random_add_noise(&pt, sizeof(pt));
126 GlobalMemoryStatus(&memstat);
127 random_add_noise(&memstat, sizeof(memstat));
129 GetThreadTimes(GetCurrentThread(), times, times + 1, times + 2,
131 random_add_noise(×, sizeof(times));
132 GetProcessTimes(GetCurrentProcess(), times, times + 1, times + 2,
134 random_add_noise(×, sizeof(times));
138 * This function is called on every keypress or mouse move, and
139 * will add the current Windows time and performance monitor
140 * counter to the noise pool. It gets the scan code or mouse
141 * position passed in.
143 void noise_ultralight(unsigned long data)
146 LARGE_INTEGER perftime;
148 random_add_noise(&data, sizeof(DWORD));
150 wintime = GetTickCount();
151 random_add_noise(&wintime, sizeof(DWORD));
153 if (QueryPerformanceCounter(&perftime))
154 random_add_noise(&perftime, sizeof(perftime));